Analog Devices

The LTC3787 is a high performance PolyPhase®single output synchronous boost converter controller that drives two N-channel power MOSFET stages out-of-phase. Multiphase operation reduces input and output capacitor requirements and allows the use of smaller inductors than the single-phase equivalent. Synchronous rectification increases efficiency, reduces power losses and eases thermal requirements, enabling high power boost applications.A 4.5V to 38V input supply range encompasses a wide range of system architectures and battery chemistries. When biased from the output of the boost converter or another auxiliary supply, the LTC3787 can operate from an input supply as low as 2.5V after start-up. The operating frequency can be set for a 50kHz to 900kHz range or synchronized to an external clock using the internal PLL. PolyPhase operation allows the LTC3787 to be configured for 2-, 3-, 4-, 6- and 12-phase operation.The SS pin ramps the output voltage during start-up. The PLLIN/MODE pin selects Burst Mode®operation, pulse- skipping mode or forced continuous mode at light loads.APPLICATIONSIndustrialAutomotiveMedicalMilitary

The LTC3788 is a high performance 2-phase dual synchronous boost converter controller that drives all N-channel power MOSFETs. Synchronous rectification increases efficiency, reduces power losses and eases thermal requirements, allowing the LTC3788 to be used in high power boost applications.A constant-frequency current mode architecture allows a phase-lockable frequency of up to 850kHz. OPTI-LOOP®compensation allows the transient response to be optimized over a wide range of output capacitance and ESR values. The LTC3788 features a precision 1.2V reference and dual power good output indicators. A 4.5V to 38V input supply range encompasses a wide range of system architectures and battery chemistries.Independent SS pins for each controller ramp the output voltages during start-up. The PLLIN/MODE pin selects among Burst Mode®operation, pulse-skipping mode or continuous inductor current mode at light loads.For a leaded 28-lead SSOP package with a fixed current limit and one PGOOD output, without phase modulation or a clock output, see the LTC3788-1 data sheet.CLKOUT/PHASMDAdjustable Current SensePower GoodPackageLTC3788YesYes25 × 5 QFN-32LTC3788-1NoNo1SSOP-28ApplicationsIndustrialAutomotiveMedicalMilitary

The LTC3789 is a high performance buck-boost switching regulator controller that operates from input voltages above, below or equal to the output voltage. The constant-frequency, current mode architecture allows a phase-lockable frequency of up to 600kHz, while an output current feedback loop provides support for battery charging. With a wide 4V to 38V (40V maximum) input and output range and seamless, low noise transitions between operating regions, the LTC3789 is ideal for automotive, telecom and battery-powered systems.The operating mode of the controller is determined through the MODE/PLLIN pin. The MODE/PLLIN pin can select between pulse-skipping mode and forced continuous mode operation and allows the IC to be synchronized to an external clock. Pulse-skipping mode offers high efficiency and low ripple at light loads, while forced continuous mode operates at a constant frequency for noise-sensitive applications.A PGOOD pin indicates when the output is within 10% of its designed set point. The LTC3789 is available in low profile 28-pin 4mm × 5mm QFN and narrow SSOP packages.ApplicationsAutomotive SystemsDistributed DC Power SystemsHigh Power Battery-Operated DevicesIndustrial Control

The LTC3802 is a dual switching regulator controller optimized for high efficiency step-down conversion from input voltages between 3V to 30V. The controller uses a leading edge modulation scheme to allow extremely low duty cycle operation. The constant frequency voltage mode controller allows a phase-lockable frequency between 330kHz and 750kHz. Power loss and noise due to the ESR of the input capacitors are minimized by operating the two controller output stages 180° out of phase. The synchronous buck architecture automatically shifts to Burst Mode operation as the output load decreases, ensuring maximum efficiency over a wide range of load currents.The LTC3802 features an onboard, trimmed 0.6V reference and provides better than 1% regulation at the converter outputs. A separate output sense provides real time overvoltage protection and PGOOD sensing. An FBT pin programs the power-up/-down tracking between the two channels to meet various sequencing requirements. A RUN/SS pin provides soft-start and externally programmable current limit protection functions.U.S. Patent Nos 5481178, 5846544, 6304066, 6580258, 5055767, 6307356ApplicationsNotebook and Palmtop ComputersPortable InstrumentsBattery-Operated Digital DevicesDC Power Distribution Systems

The LTC3803-3 is a constant frequency current mode flyback controller optimized for driving N-channel MOSFETs in high input voltage applications. Constant frequency operation is maintained down to very light loads, resulting in less low frequency noise generation over a wide range of load currents. Slope compensation can be programmed with an external resistor.The LTC3803-3 provides ±1.5% output voltage accuracy and consumes only 240μA of quiescent current. Ground referenced current sensing allows LTC3803-3-based converters to accept input supplies beyond the LTC3803-3’s absolute maximum VCC. A micropower hysteretic start-up feature allows efficient operation at high input voltages. For simplicity, the LTC3803-3 can also be powered from a high VINthrough a resistor, due to its internal shunt regulator. An internal undervoltage lockout shuts down the LTC3803-3 when the input voltage is too low to provide sufficient gate drive to the external MOSFET.The LTC3803-3 is available in a low profile (1mm) 6-lead SOT-23 (ThinSOT™) package.Turn On VoltageFrequencyLTC38038.7V200kHzLTC3803-38.7V300kHzLTC3803-54.8V200kHzApplicationsTelecom Power Supplies42V and 12V Automotive Power SuppliesAuxiliary/Housekeeping Power SuppliesPower over Ethernet Powered Devices

The LTC3805-5 is a current mode DC/DC controller designed to drive an N-channel MOSFET in flyback, boost and SEPIC converter applications. Operating frequency and slope compensation can be programmed by external resistors. Programmable overcurrent sensing protects the converter from overload and short-circuit conditions. Soft-start can be programmed using an external capacitor and the soft-start capacitor also programs an automatic restart feature.The LTC3805-5 provides ±1.5% output voltage accuracy and consumes only 360μA of quiescent current during normal operation and only 40μA during micropower startup. Using a 9.5V internal shunt regulator, the LTC3805-5 can be powered from a high VINthrough a resistor or it can be powered directly from a low impedance DC voltage from 4.7V to 8.8V.The LTC3805-5 is available in the 10-lead MSOP package and the 3mm × 3mm DFN package.Turn On VoltageLTC38058.4VLTC3805-54.5VApplicationsAutomotive Power SuppliesTelecom Power SuppliesIsolated Electronic EquipmentAuxiliary/Housekeeping Power SuppliesPower over Ethernet

The LTC3806 is a current mode synchronous flyback controller that drives N-channel power MOSFETs and requires very few external components. It is intended for medium power applications where multiple outputs are required. Synchronous rectification provides higher efficiency and improved output cross regulation than nonsynchronous converters.The IC contains all the necessary control circuitry including a 250kHz oscillator, precision undervoltage lockout circuit with hysteresis, gate drivers for primary and synchronous switches, current mode control circuitry and soft-start circuitry.Programmable soft-start reduces inrush currents. This makes it easier to design compliant Power Over Ethernet supplies.Low start-up current reduces power dissipation in the start-up resistor and reduces the size of the external startup capacitor.The LTC3806 is available in a 12-pin, exposed pad DFN package.Applications48V Telecom Supplies12V/42V Automotive24V IndustrialVoIP PhonePower Over Ethernet

The LTC3807 is a high performance step-down switching regulator DC/DC controller that drives an all N-channel synchronous power MOSFET stage. A constant frequency current mode architecture allows a phase-lockable frequency of up to 750kHz.The 50μA no-load quiescent current extends operating run time in battery-powered systems. OPTI-LOOP®compensation allows the transient response to be optimized over a wide range of output capacitance and ESR values. The LTC3807 features a precision 0.8V reference and power good output indicator. A wide 4V to 38V input supply range encompasses a wide range of intermediate bus voltages and battery chemistries. The output voltage of the LTC3807 can be programmed between 0.8V to 24V.The TRACK/SS pin ramps the output voltages during start-up. Current foldback limits MOSFET heat dissipation during short-circuit conditions. The PLLIN/MODE pin selects among Burst Mode operation, pulse-skipping mode, or continuous conduction mode at light loads.ApplicationsAutomotive Always-On SystemsBattery Powered Digital DevicesDistributed DC Power Systems

The LTC3808 is a synchronous step-down switching regulator controller that drives external complementary power MOSFETs using few external components. The constant frequency current mode architecture with MOSFET VDSsensing eliminates the need for a current sense resistor and improves efficiency.Burst Mode operation provides high efficiency operation at light loads. 100% duty cycle provides low dropout operation, extending operating time in battery-powered systems.The switching frequency can be programmed up to 750kHz, allowing the use of small surface mount inductors and capacitors. For noise sensitive applications, the LTC3808 can be externally synchronized from 250kHz to 750kHz. Burst Mode is inhibited during synchronization or when the SYNC/MODE pin is pulled low to reduce noise and RF interference. To further reduce EMI, the LTC3808 incorporates a novel spread spectrum frequency modulation technique.The LTC3808 is available in the tiny footprint thermally enhanced DFN package or 16-lead SSOP package.Protected by U.S. Patents including 5481178, 5929620, 6580258, 6304066, 5847554, 6611131, 6498466. Other Patents pending.FeaturesPackageLTC3809PLL, Selectable Spread Spectrum, Power Good3x3 DFN-10, MS-10ELTC3809-1Tracking3x3 DFN-10, MS-10ELTC3808PLL, Selectable Spread Spectrum, Tracking Power Good4x3 DFN-14, SSOP-16ApplicationsOne or Two Cell Lithium-Ion Powered DevicesNotebook and Palmtop Computers, PDAsPortable InstrumentsDistributed DC Power Systems

The LTC3809 is a synchronous step-down switching regulator controller that drives external complementary power MOSFETs using few external components. The constant frequency current mode architecture with MOSFET VDSsensing eliminates the need for a current sense resistor and improves efficiency.For noise sensitive applications, the LTC3809 can be externally synchronized from 250kHz to 750kHz. Burst Mode is inhibited during synchronization or when the SYNC/MODE pin is pulled low to reduce noise and RF interference. To further reduce EMI, the LTC3809 incorporates a novel spread spectrum frequency modulation technique.Burst Mode operation provides high efficiency operation at light loads. 100% duty cycle provides low dropout operation, extending operating time in battery-powered systems.The switching frequency can be programmed up to 750kHz, allowing the use of small surface mount inductors and capacitors.The LTC3809 is available in the tiny footprint thermally enhanced DFN and 10-lead MSOP packages.FeaturesPackageLTC3809PLL, Selectable Spread Spectrum, Power Good3x3 DFN-10, MS-10ELTC3809-1Tracking3x3 DFN-10, MS-10ELTC3808PLL, Selectable Spread Spectrum, Tracking, Power Good4x3 DFN-14, SSOP-16Applications1- or 2-Cell Lithium-Ion Powered DevicesPortable InstrumentsDistributed DC Power Systems